Stirring Things Up: SRC Advances Metal Smelting Technology

Date Posted

pouring molten rare earth metals into an ingot mold at src

The Saskatchewan Research Council (SRC) is reinventing the traditional method of mixing and manufacturing metals with innovative advancements in metal smelting technology — an integral part of SRC’s minerals-to-metals Rare Earth Processing Facility, which is nearing completion in late 2024.

SRC’s advancements in metal smelting are two-fold: focusing on safety, while operating and consistently producing commercial-grade rare earth metals. 

Imagine spending 12 hours a day encased in an aluminized suit. Your vision limited to the small window of your face shield. Inside the suit, layers of heat-resistant-clothing — long-sleeves, glasses, gloves, earplugs and a respirator — provide you with the protection you need. This is what is typically required for the traditional metal manufacturing process known as metal smelting

“SRC is taking the human element away from working in front of the 1,100 Celsius furnace, allowing someone to instead control the automatic mixing instruments developed in-house from a safe distance,” says Dr. Muhammad Imran, Vice-President of the Rare Earth Elements (REE) Division at SRC. 

“When you look at the conventional way of producing metals, its success depends on skilled staff and that skill is built on decades of experience.” 

Developing new, safer ways to manufacture metals

Historically, it’s been a person at the helm, equipped in personal protective equipment (PPE), armed with a giant heat-resistant stirring stick, moving the liquid metal back and forth repeatedly. 

Once the operator feels the mixture has reached the right consistency, the precious metals can be extracted and poured into metal molds.

“Instead of just relying on people to qualify the product as commercial grade, we are relying on the equipment developed at SRC,” Dr. Imran says. “If we don't do that, maintaining high safety standards and product quality becomes a challenge.”

Thanks to a $3-million investment from Prairies Economic Development Canada (PrairiesCan), engineers in SRC’s REE Division designed and manufactured an automatic stirring instrument that mixes the molten liquid until the metals have reached commercial-grade purity. The stirring instrument is unique because it delivers two kinds of stirring patterns, mimicking how the earth rotates on its own axis as well as around the sun, with the earth representing the mixing instrument and the sun representing the centre of the furnace. 

The instrument moving around the furnace in a tight, constant motion kickstarts the chemical process as more rare earth oxides are added to the mixture. The continuous motion helps avoid sludge formations inside.

“It stirs, as well as moves across the whole vessel, in a very confined space at very high temperatures,” Dr. Imran says. “This is the unique intellectual property that SRC has developed.”

Eliminating variables, ensuring greatest recovery and metal purity

rare earth ingots produced at src

Ensuring consistency throughout the smelting process results in the production of commercial-grade metals. If the process encounters variables, the end product fails to meet the recovery and purity targets. 

“If the process conditions are not set right, if the temperature is not within the given range and sludge forms, you miss out on recovering the REEs,” Dr. Imran says. “You don't convert all of the rare earth oxides into metals and that leads to downgrades in purity.” 

SRC’s Rare Earth Processing Facility is capable of producing neodymium-praseodymium (NdPr) metals with 99 per cent purity, something Dr. Imran says would be at risk if the smelting process was left to the manual process.

With semi-automation already steering the mixing process, similar technology is being adopted by SRC to measure, add and track the time rare earth oxides spend in the smelter. 

In order to produce the metals needed to manufacture permanent magnets, Dr. Imran says rare earth oxides are added to the mixture at precise intervals, something that would be difficult to track manually. 

“The system automates the process of feeding the rare earth oxides into the furnace and lets the furnace operators know when the oxides have reduced to metal,” Dr. Imran says. “This requires incredible precision and is difficult for individuals to replicate.”

Dr. Imran explained that once the rare earths are added to the furnace, metals are produced within three to four hours. Imran says eventually SRC’s goal is to automate the extraction process as well. 

“To achieve the end goal of producing pure metals from REEs, the crux of the operation depends on manufacturing a consistent end product,” Dr. Imran says. 

New technology driving up productivity, de-risking the operation

src logo on its proprietary metal smelting furnace

When SRC first embarked on developing Canada’s first Rare Earth Processing Facility in 2020, the scope involved a monazite processing unit and solvent extraction unit. Since then, global market volatility around REEs proved to be more unstable over time. 

“This forced SRC to think, how can we innovate?” Dr. Imran says. “We started to look into the possibilities of improving our operations, reducing operating costs and looking at how SRC could withstand market volatility.”

Originally, this automated stirring instrument, and smelting equipment wasn’t in the project scope. But now, as the processing facility nears completion, the addition of this technology increases the safety of the facility by removing the operator from standing in front of the smelter. At the same time, this increases the productivity of the smelting process, ensuring consistency throughout, which results in the purest metals possible. 

And there’s more to come. 

“At this point, it is automatic stirring but soon it will be automatic extraction, sampling and storage, and it will be AI-controlled,” Dr. Imran says, adding SRC has already developed artificial intelligence technology to control its Solvent Extraction Unit, with metal smelting being another step towards full automation. 

“The objective is to address the risk of market volatility. It’s really about the economics. If we focus on automation and recovery and product consistency in the metal manufacturing process, then the operation, from beginning to end, can be economically viable.”

In 2020, SRC’s Rare Earth Processing Facility was an ambitious proposition. Now in 2024, SRC is on the cusp of producing its first commercial round of 99 per cent pure NdPr metals. An achievement Dr. Imran says humbles him, knowing all the work poured into the project over the past four years. 

SRC’s dedication to innovation pivotal to REE Facility’s success

an src employee operating src's proprietary metal smelting furnace

The automation advancement in the metal smelting unit is just the latest innovation from SRC’s research and development team. In 2023, SRC successfully designed and manufactured proprietary, commercial-scale solvent extraction cells for its Rare Earth Processing Facility, adding Saskatchewan to only a handful of jurisdictions in the world with this capability. 

SRC’s solvent extraction fabrication facility also adopted a unique plastic welding technique to manufacture its separation cells for its facility, something not widely used, but a trade that’s growing in the construction sector. 

“I'm privileged to work with the team we have right now,” Dr. Imran says. “There is no doubt we wouldn’t be able to achieve all these great accomplishments across the rare earth sector without such a skilled, talented and entrepreneurial team.” 

Once SRC flips the switch on its Rare Earth Processing Facility, it will act as the pilot light for a rare earth hub in Saskatchewan. Equipped with its three-stage, fully integrated process, including monazite processing, proprietary solvent extraction and metal smelting components, the Facility will be producing enough rare earth metals to power half a million electric vehicles a year.