Diminishing ore grades can be the scourge of the resources sector, but FLSmidth has stepped up to help miners get the most out of what they dig up.
Many would be familiar with FLSmidth’s (FLS) Reflux Classifier (RC), an advanced gravity-based separator that allows miners to separate particles based on size and density.
But as the mining industry continues to face the challenge of diminishing ore grades, which is somewhat paradoxically coupled with an increased demand for metals, lower-grade ores and tailings must be processed to extract the minerals needed.
FLS understands this challenge, and that understanding was behind the decision to start the process of refining its RC technology into the REFLUX Classifying Concentrator (RCC).
“By reducing the size of the mixing chamber and introducing a split fluidisation water system in the RCC, we can accommodate low-grade markets,” FLSmidth product line manager – global Nicolas Boonzaier told Australian Mining.
“We’ve been busy collaborating with our stakeholders, lab partners and engineers to create technology we know will work for our customers.”
Valuable minerals can certainly still be found in low-grade ore, but processing them can be costly and capital intensive.
But with the RCC, FLS has developed a way to overcome this situation.
“In the testing phase of development, we put the RCC toe-to-toe with the RC and had both process low-grade ore,” Boonzaier said.
“We were really pleased with the results. We had close to a 200 per cent improvement in processing from the RCC.
“The photos taken from the samples were very telling. In the one from the RC, you can see a lot of lighter-coloured silica but in the RCC, the sample is all black, which is an indication that it has rejected all the gangue, or waste, particles.”
The RCC features secondary fluidisation water above the bed, augmenting upward flux without disturbing the bed and removing lightweight gangue particles.
This feature increases the selectivity of particles that form part of the bed, which results in a higher quality and more dense bed.
“This feature is something that adds real value to the technology,” Boonzaier said. “It means the existing bed is not going to be disturbed, and we can create an upward flux that will reject the particles before they can enter the bed.
“I’m quite excited to see how we can continue to use this concept in our existing product lines.”
FLS is dedicated to the continuous improvement of its technologies. Boonzaier is particularly proud of the fact the development of the RCC has given miners the ability to process low-grade ore that would have previously been discarded.
“These low-grade streams are sometimes considered not economically viable because of the capital outlay that’s required to process them,” he said.
“I’m extremely confident that with the RCC, customers can turn something that was once wasteful into an economically viable project.
“This development really stands in line with FLS’s ethical obligation towards environmental sustainability.”
Using the original RC as a jumping off point for the RCC technology, FLS was able to understand what would and would not work in the new iteration.
“If you look at what the RC looked like in 2005, and then 2010, 2015, 2019 … you can see the continuous updates it’s gone through,” Boonzaier said.
“We were able to have and use consistent feedback from our customers, and actually travel to the sites ourselves to see how our designs can be improved.
“When we commission a new unit, I typically go out onsite myself and make the observations on how our technologies can work with the site, then I take that back to the engineers.
“It’s in our DNA to collaborate and brainstorm ways of overcoming challenges that our customers might have, and the RCC is another way we’ve done this.”
This feature appeared in the November 2023 issue of Australian Mining.