Sudbury may be on the cusp of an innovative new phase in its 40-year regreening effort.
What an army of volunteer tree planters once accomplished to reforest a barren landscape, blackened by a century of nickel roasting and smelting, now a swarm of microscopic bugs could provide in an environmentally friendly solution to clean up a massive amount of mined waste rock while recovering valuable minerals in the process.
BacTech Environmental Corp., a Toronto green technology company, is pulling a proven technology out of mothballs to relaunch it in Sudbury to “liberate” millions of dollars worth of battery-grade metals out of mine tailings through a proprietary bioleaching process.
The company estimates the Sudbury basin hosts up to 100 million tonnes of pyrrohotite concentrate, mostly held by Vale and Glencore in tailings areas, containing valuable nickel and cobalt. Both are deemed critical minerals in the electric vehicle battery supply chain.
BacTech estimates there’s US$22 billion worth of untapped nickel, based on the market price for nickel at US$27,000 per tonne. The tailings are estimated to contain 0.80 per nickel and 0.03 per cent cobalt.
"People get excited about 0.25 per cent in a drill hole," said Ross Orr, BacTech's president-CEO. "This is three times that, and it's sitting at surface."
The company is working with Sudbury microbiologist Nadia Mykytczuk to assemble the components for a pyrrohotite pilot processing plant on the campus. Filling a space the size of a two-car garage, it's expected to be operational by July.
Pyrrohotite (pronounced pir-uh-tayht) is an iron sulphide material containing low levels of nickel, cobalt and copper. During the mill flotation process, it separates from the more valuable pentlandite and is typically dismissed as an uneconomical waste byproduct into a tailings storage area.
Besides the targeted nickel and cobalt BacTech would be pursuing, Orr said there's a raft of other saleable minerals, like silicates, in the mix as well.
While the company is far from striking any deals with Sudbury's major mining companies, to Orr, the Nickel City is the ideal place to showcase this technology.
“It has to be cleaned up and you gotta believe that the big guys (the mining companies) are rubbing their hands together and would love to get their hands on the nickel that’s left behind."
BacTech occupies a niche industry sector known as bio-mining. They don’t do any actual mining. They buy concentrate that’s already been mined and extract the valuable minerals from it.
As one of only two companies in the world engaged in bioleaching, the company has made great strides in extracting gold and remediating old tailings piles in Ecuador.
This past spring, BacTech pocketed a permit from Ecuador’s Ministry of Energy and Mines to build a $17-million commercial-scale bioleaching facility in the Ponce Enriquez region for treating high gold and arsenic material. The company is also making inroads into Peru and Colombia to set up similar facilities.
With Sudbury, BacTech has been collaborating with Mykytczuk, a leading expert on bioleaching and bioremediation, who serves as interim president at MIRARCO, an independent applied research corporation at Laurentian. She serves on BacTech's advisory board.
Mykytczuk views the pilot plant is the first step in her goal of creating a whole new mining industry in Sudbury, centred around bioremediation.
She has greater aspirations of establishing a Centre of Mine Waste Biotechnology, her brainchild-in-the-making over the last three years for a proposed research and commercialization hub.
"It's part one of a larger effort but it'll be the workhorse to test different bioleaching processes for different minerals," she said.
Mykytczuk will present the centre's business case at the BEV In Depth Conference in Sudbury this week..
For the pilot plant, which she ballparks at “several hundred thousand dollars,” Mykytczuk intends to tap into federal funding through the new Critical Minerals Research, Development and Demonstration Program.
It’s a $10.95-million funding pot within a deeper pool of $47.7 million set aside in the federal budget to fund innovative green processing and refining technologies for the battery mineral market in Canada.
At the same time, BacTech has applied for a process patent application for the pyrrhotite bioleaching process, specifically geared to treat Sudbury tailings.
The bioleaching process involves using naturally occurring and harmless bacteria to target certain ores and contain other substances that are harmful to humans.
Using the promotional tag line of “Our Bugs Eat Rocks!”, BacTech uses the analogy of a brick wall, comparing the sulphides to the mortar holding the minerals together in the rock. Their bacteria chews through and oxidizes the sulphides, freeing the high-value metals that the company is after.
At Laurentian, Mykytczuk and her graduate students collect the bacteria from tailings piles and stimulate them to thrive and multiply in a series of bioreactor tanks. Under favourable conditions, the bug can work in their magic in less than a week in what normally would take decades in the natural world.
One favourable byproduct that streams out their Ecuador bioleaching process is a stable form of arsenic that can be landfilled.
The whole process eliminates environmentally harmful smelting and roasting techniques used today and in the past by the mining industry.
The data pulled from the pilot plant would be applied toward a larger acre-sized demonstration plant built, handling greater tonnages, and costing $10 million to $15 million to construct, said Orr.
To graduate up to actual commercial-scale plant would require an industrial park-sized “farm” of stainless steel tanks, Orr said, potentially employing hundreds of people..
Orr said if his company had access to Sudbury tailings, and had the financing and brownfield space for a 10,000-tonne-a-day processing plant, they could conceivably create a 25-year operation.
“That is one big honking bioleach plant.”
He expressed confidence that this technology can be adapted to recover run a wide range of mineral commodities of economic value.
The pyrrhotite bioleaching process has been in BacTech's backpocket for decades.
A company shareholder, Paul Miller, vice-president of technology, built a pyrrhotite pilot plant more than 20 years ago in Western Australia. Miller is regarded as one of the world’s pre-eminent bioleaching experts.
Pulling the nickel and cobalt out of the tailings proved to be an easy feat — recovery rates were 99 per cent — but the process produced one large byproduct, an excessive amount of iron.
But at that time, they couldn’t make the economics work; now they’re dusting it off to try in Sudbury.
Not lost on BacTech is the fact that Algoma Steel in Sault Ste. Marie is only 300 kilometres west of the city, connected by rail.
Orr views Algoma as a potential customer for an iron compound as an alternative for iron ore. The steelmaker is on a ‘green steel’ movement in transitioning from coal-burned steelmaking to electric arc furnace technology in the next few years.
“This is just another arrow in their quiver,” said Orr. “But we have to produce a product that will be acceptable to them.”
Extracting minerals using bioleaching has been widely known in mining circles for years. Regarded as a cool, green technology, there’s been a reluctance by industry and investors to take the plunge.
That’s all changed in the last year.
Society demands that resource extraction companies operate in a environmentally and socially responsible way. Moreover, there’s a global scramble by mining companies and electric vehicle manufacturers to secure supplies of critical minerals used in battery production. Canada is considered a good place to lock up those resources.
And governments at all levels are incentivizing the use of green technologies to create net zero carbon economies.
For Mykytczuk, getting the pilot plant going and securing government funding to prove their process might attract big project players to the table, namely Glencore and Vale.
And if MIRARCO can tap into additional funding to build the centre over the next two years, the technology might be transferred to an industrial park.
The construction of a pilot plant represents a breakthrough for Mykytczuk in the direction of her research career since arriving in Sudbury 17 years ago.
“The use of biotechnology in mining has been such a niche application in my whole career and yet we’re suddenly on this very rapid shift toward critical minerals and electrification,” she said.
“There’s a need for these technologies and a real opportunity, and it’s very exciting because it reinforces what I’ve worked on for so long. This isn’t some academic pursuit that never leaves the bench. It’s actually got a lotta potential to make a real difference and be part of this clean energy transition that’s going to come at us very quickly.”