The high-tech vision for the world’s first smart mineral processing plant will see integrated data technologies enable automated production. TIM THWAITES reports
Satellite navigation and mapping, autonomous processes, robotic excavators, mineral sensing equipment, smart safety devices, intelligent control of metal extraction – that's where Australia's mining industry needs to be headed.
It's a long way from digging a hole in the ground in the right place and shipping the contents overseas; the future is in investing in smart technology.
As Australia's Chief Scientist, Dr Alan Finkel, said recently in an Australian Institute of Mining and Metallurgy lecture: "good luck building an intelligent mine in a data black hole."
It's a black hole that CSIRO has been working on for decades to plug.
Smart sensors to transform mineral processing
CSIRO's efforts have started to bear fruit in the processing space, with smart sensing technology solutions such as their magnetic resonance ore sorter, which within seconds, can distinguish productive copper ore from waste.
CSIRO has also developed gold analysis techniques, including an alternative to fire assay that can determine the levels in ore of gold and many other metals of low natural concentrations within a few minutes; and the Online Gold Analyser (OLGA), which can determine gold concentrations in process streams to less than one part per million.
The potential impact of these sensors, and other digital advances on the way could be revolutionary, CSIRO Mineral Resources director, Jonathan Law, says.
"This sort of technology could rewrite the whole triple bottom line equation," he says.
"The benefits flow right through the value chain – defining what resources really look like in situ, mining them in a more focused way, sorting the material before it gets processed, and making sure the processing is controlled and efficient. And, finally these tools can be used to understand, monitor and control environmental outcomes.
"So, you spend less capital by building smaller processing plants because you are more efficient, and you reduce environmental impacts because you know exactly what you are putting out there and in smaller volumes."
Mineral producers still need to tackle industry 3.0
Mr Law envisages an industry improving its efficiency initially by introducing smart technology into individual processes (industry 3.0). And then, combining and integrating these processes into automated production (industry 4.0) – similar to the manufacturing industry but with the orebody rather than the manufactured product being the key driver. But, he recognises there are still significant barriers to negotiate.
Manufacturers can specify their feed materials within precise tolerances and design their factories to suit; they can measure all their inputs and reject anything out-of-specification.
"In mining, every mineral, every ore and every minesite is different. We can't be like manufacturing until we can measure key things," Mineralis Consultants senior minerals industry adviser, Joe Pease, says.
Different needs for bulk versus precious metal commodities
CSIRO fellow Dr Ray Shaw, another industry insider, says the needs of bulk ore miners – such as iron ore, bauxite and coal producers – are very different from those who produce metals such as gold, copper and platinum where natural concentrations are low.
The processing of bulk materials focuses heavily on grade control through blending, and therefore, technologies that determine the composition of the ore are important. Extracting precious metals, however, puts the emphasis on controlling the process itself, as well as the ore feed.
The flexibility of the latest developments in digital technology and in analysis, have allowed CSIRO to come up with a whole range of helpful sensors. For example, WI-SED automatically tracks progress of sedimentation and sends the results via Wi-Fi to a computer or smartphone; whereas InterFloat monitors froth depth in mineral floatation units.
They have also developed SENSEI technology, which incorporates robust, solid-state electrochemical sensors that can be embedded in materials being processed in order to transmit measurements of properties, such as temperature, conductivity, pH or levels of dissolved metal ions.
"All of these are at least at the prototype demonstration stage and are being tested on mining operations around the world," Mr Law says.
A step change in copper production
The CSIRO-developed magnetic resonance technology for ore sorting – commercialised through NextOre – heralds big changes. It analyses and sorts without interruption to a flow of 5000 tonnes an hour of copper-bearing rock from mine to stockpile or process plant.
This technology fires short pulse radio waves into the rock and within seconds, using magnetic resonance technology similar to a medical MRI, it can determine the form and amount of copper moving past. Once identified, a separate diverter can reject the gangue before it enters the processing chain, saving energy and water otherwise wasted on unproductive ore.
NextOre's ore sorting solution can save in the order of 20 per cent of costs, which equates to a lot of money for a plant costing tens or hundreds of millions of dollars a year to operate.
It is already on the market, sold not simply as sensing equipment, but as a packaged solution that can undertake the analysis and provide information for rapid decision-making. It can be added or bolted on to existing operations.
Paving the way for new plant designs
Other new sensors for mineral processing may enable different plant designs, and different organisational approaches.
"If we don’t know what is coming into the plant, then natural ore variation is harmful. So the best strategy is to smooth out the variation by lumping everything together to get average performance," Mr Pease says.
"With real-time knowledge of input, we could put the variation to our advantage and optimise the plant for each kind or ore. This would change the way we design and operate mines and plants."
According to Dr Shaw, one problem is that many companies have cut down on the number of people dealing with the technical side of their business and have contracted out these skills, so they might need to buy in knowledge to assess and handle the new technology. And, new technology is always a risk.
"Added to all the geological, political, social and approval risks of a mine, is it reasonable to ask the Board to assume another risk – that of technology? Once an early adopter demonstrates that the technology is robust, can be applied and makes money, it will be adopted quickly," Mr Pease adds.
The next big gains, probably lie in data management, particularly in the development of packages that integrate sensors to produce a more comprehensive picture of what is happening, allowing finer control and better optimisation.
"CSIRO Mineral Resources is beginning to look at that in conjunction with CSIRO's data innovation powerhouse Data61," Mr Law says.
"There is huge opportunity to transform the industry."