The coming age of preconcentration
A CRC ORE breakthrough in the preconcentration space will potentially change the way mining has been undertaken for decades.
This is an excerpt from an Australian Mining article (February 2021), written by Vanessa Zhou.
The Brisbane-based Cooperative Research Centre for Optimising Resource Extraction (CRC ORE) has introduced a suite of technologies that could integrate the value of preconcentration into an entire mining value chain.
Describing its Grade Engineering suite of technologies as a gamechanger, the effective inclusion of preconcentration it enables can truly boost mine life and dramatically reduce a miner’s operational costs.
Grade Engineering technologies, now exclusively commercialised by Hatch, enable waste material to be removed from ore at different stages of the mining process.
The removal of waste is achieved by using screens to separate based on size, sensors to separate based on physical properties or jigs to separate based on density differences, according to CRC ORE chief operating officer Luke Keeney.
“In a conventional operation, ore is mined and then all of it is sent to the concentrator. With Grade Engineering, some of the ore undergoes preconcentration and only a component of the mined ore is sent to the concentrator. This component is depleted in waste and increased in metal content,” Keeney tells Australian Mining.
“This changes the material movement flows around an operation and changes the characteristics of the feed to the concentrator, which will have metallurgical impacts.”
Grade Engineering is capable of matching a suite of separation technologies to ore specific characteristics and comparing the net value of rejecting low value components in current feed streams to existing mine plans.
“Our achievement in preconcentration has been around systemising and standardising the approach for industry to assess the preconcentration opportunities, from desktop studies to value-add opportunities, all the way through to production trials where you’re demonstrating the impact and value on site,” Keeney says.
“In the past, there’s been a lot of solutions made, but they all failed because the impact of preconcentration is so broad that you need to evaluate it in such a way.”
BHP has engaged CRC ORE to examine bulk ore sensing and opportunities that fit within the Grade Engineering suite of technologies at the Olympic Dam polymetallic mine in South Australia.
The two companies have explored sublevel open stoping under the current mining environment, along with block caving as part of future-state mining options.
Beyond finding bulk ore opportunities, Keeney believes the effective inclusion of preconcentration in mine design can have a profound impact on mine functions.
“The real benefit of putting in preconcentration in existing mine operations absolutely adds value, but it is also more challenging to retrofit existing operations with new pre-concentration technologies,” he says.
“However, the real benefit – and this is where the mining industry is going – is where next generation mines will start to be built and include preconcentration from the beginning.”
The concept of preconcentration existed long before CRC ORE was established, but the research centre may be the first to integrate all the necessary technologies into the mining value chain that involves screens, sensors, jigs and others.
This way, the impact of preconcentration on an entire mining operation can be modelled and quantified.
It allows mining companies to truly understand how to build its ore resource models and gauge the impact of including preconcentration on material movement and productivity.
Mining companies can also use much smaller equipment to produce the same metal, slashing capital intensity and dramatically changing a mine’s economics.
Other huge benefits for the taking include increased feed grades, lower operational costs, higher conversion from resources to reserves and lower energy and water intensity.
“The industry is becoming increasingly aware of the benefits preconcentration provides in reducing energy and water intensities. These benefits are intimately linked to global social licence to operate challenges,” Keeney says.
The inclusion of preconcentration also means that mining zones previously outside of the mine life, or those considered subeconomic or not able to be extracted from can now come into the picture, giving a mine a much longer life.
Deposits that were previously very difficult to attain also now become more appealing, according to Keeney.
“CRC ORE has worked very closely with mining participants – the end users – and we’ve really understood what the fundamental challenges are when implementing preconcentration strategies on operation,” Keeney says.
“We’re not trying to push a solution or looking for a home for our technologies, but we know what the industry problem is and customise the solution for that problem.”
With this thorough understanding, CRC ORE has also developed its second primary technology suite, named Integrated Extraction Simulator (IES).
The IES is a cloud-based system software platform where everything from blasting through to concentrate can be modelled in one simulation environment.
Working hand in hand with CRC ORE’s Grade Engineering, Keeney says IES gives mining operators the ability to do millions of simulations to understand all of its options, where bottlenecks might be occurring and to combine all those factors in the process.
“We’ve been very successful in taking an integrated approach … (as) we’ve really understood how to evaluate everything from resource model through to concentrate production, in terms of how we model deposits, how we change the material movements into the system and the impact on concentrators,” he explains.
“If you’re applying preconcentration technologies to a site, it kicks in on how we blast, crush, grind and process the rocks through to concentrator.
“We can model the response of the ore, what equipment we need to deliver the preconcentration technology, and also understand what the impacts are on the concentrator. Because at the end of the day, that’s where mines get their money from.”
Contradicting the beliefs of some that cooperative research centres run in competition with mining equipment, technology and services (METS) companies, Keeney argues that conversely, CRC ORE aims to work with mining companies to implement its technologies, with the support of the METS sector.
“They’re the ones providing the service to mining companies, so we get the three groups working together. That’s been one reason why CRC ORE has been so successful. We harness that ecosystem and get everyone working together,” Keeney says.
“CRC ORE simply operates like a translator or intermediary in that process.”
This role is definitely not understated, as its technologies hold a tremendous power to change the game in the mining sector.
“We still have challenges around productivity, energy, water usage and intensity. While doing more of the same and becoming more efficient are all good, they’re not helping us to make the step change to the social challenges we are facing. On the other hand, the inclusion of preconcentration offers the opportunity to do that,” Keeney says.
“It’s going to be in the not-so-distant future where mines start implementing this right from the beginning of a new mine operation.”
This article also appears in the February issue of Australian Mining.