BCGS Symposium: Minds gather in Canada for rare earths research

By James Sean Dickson
Published: Friday, 27 November 2015

Metallurgy remains barrier to market entry, but new technology is a big risk game.

The British Columbia Geological Survey (BCGS) Symposium on Strategic and Critical Materials in Victoria, Canada, in November saw academics from across the world gather to discuss some of the pressing challenges and opportunities facing the rare earths sector.

The conference heard that processing remains one of the main barriers to new entrants in the rare earths industry.

"It takes millions of years to produce a good deposit. The good news is that a rare earth flowsheet only takes 15 years to make," Niels Verbaan, principal metallurgist at SGS Canada Inc., a technical services consultancy, quipped.

"Once a deposit has been found and described by geologists, there is still much work to be done by metallurgists for an efficient flowsheet," Verbaan added, noting that there is little operating experience to be drawn on in the Western world.

Verbaan said that a key requirement for metallurgists is full knowledge and understanding of the feed material. Rare earth ore minerals include a variety of phosphates, fluorides and cyclosilicates, each with individual processing needs.

He told IM that current rare earth industry metallurgical challenges reminded him of nickel laterite projects being developed in the 1980s.

"There was a big development rush with not enough time and money spent on metallurgy, resulting in operational difficulties," Verbaan said.

Stephen Rowins, chief geologist and executive director at the BCGS, agreed, and told IM that, in this instance, strong acids used to process the feedstock "wrecked" the plants by reacting more quickly with their equipment than was anticipated.

"There is no real alternative to acid-based separation in the rare earths industry, however," Rowins said.

Challenges for new entrants include the evolution of gelatinous silica from specific mineralogies, Alex Knox, a rare earths and limestone-focused consulting geologist at AWK Geological Consulting Ltd, said.

This problem is now solvable, however, Knox said, and several delegates suggested that high purity silica gel could even be sold as a silicon metal feedstock.

Flowsheet experimentation

For Verbaan, amelioration of complex processing difficulties could be found in additional flowsheet piloting.

"Recent entrants could have seen some more work done on acid bake piloting, though acid leaching was better advanced," he told IM.

But while new, pilot-scale processing technologies exist, like molecular recognition technology (MRT), as championed by Alaska-focused Ucore Rare Metals Inc. and free flow electrophoresis (FFE), supported by Quebec-operating Geomega Inc., they remain a gamble.

"There are big risks with new tech when upscaling," Verbaan told IM. "However, MRT seems to be the most advanced and it’s used in other industries," he concluded.