Metal Tech News - The Elements of Innovation Discovered

A mine that could suck billions of tons of carbon dioxide out of the atmosphere and turn it to stone while also producing the nickel, cobalt, and other metals needed for zero-emissions electric vehicles would be the ultimate prize for Tesla Inc. CEO Elon Musk.

Carbin Minerals and Carbfix, two companies developing just that type of technology, have been awarded $1 million from XPRIZE, a global future-positive movement envisioned by Musk and supported by his foundation.

XPRIZE provides cash awards to individuals, teams, and organizations that compete for the best ideas to tackle global challenges, from racial equality and modernizing education to restoring coral reefs and sequestering CO2.

On the CO2 front, the Musk Foundation is supporting the XPRIZE for Carbon Removal with $100 million that will go to teams with technologies that demonstrate the viability of economically removing billions of tons of CO2 from the atmosphere.

"We want to make a truly meaningful impact. Carbon negativity, not neutrality. The ultimate goal is scalable carbon extraction technologies that are measured based on the 'fully considered cost per ton' which includes the environmental impact," Musk said at the launch of XPRIZE for Carbon Removal. "This is not a theoretical competition; we want teams that will build real systems that can make a measurable impact and scale to a gigaton level. Whatever it takes. Time is of the essence."

On Earth Day 2022, XPRIZE for Carbon Removal awarded 15 milestone winning teams $1 million each for a wide array of technologies that utilize mechanical systems, agriculture, and rocks to remove CO2 from the atmosphere and oceans.

These innovative companies, judged as the most likely to be able to economically scale carbon capture up to gigaton per year levels, will be able to use the prize money earned to further advance their CO2 capturing technologies as they compete for the $80 million in grand prizes to be awarded in 2025.

Four of these XPRIZE winners are leveraging the ability of certain minerals to absorb CO2 from the atmosphere and turn it into rock, where it will be stored for geological periods of time.

Locking carbon in minerals

Carbin Minerals, a new Canadian company founded by University of British Columbia Professor Greg Dipple, is developing a technology that leverages the natural CO2 absorbing abilities of certain minerals in the tailings left behind from mining nickel, cobalt, and other metals.

This idea of locking up CO2 in this waste from mines that produce metals needed for the low-carbon future is not new to Dipple, who has been working on this technology with a team at UBC for 15 years.

Dipple realized that ultramafic rocks – igneous rock with a high magnesium and iron content – are among the largest CO2 storing reservoirs on Earth. The carbon-absorbing potential of these rocks, however, is limited when they are buried away from the atmosphere.

It so happens that rich stores of nickel and cobalt are also found in ultramafic rocks. The mining and grinding of these rocks to a sand-like consistency in order to recover the lithium-ion battery metals is a great start to maximizing their CO2 sequestering potential.

Tests recently carried out by Dipple and his team at UBC indicate that Giga Metals Corp.'s Turnagain project in Northern British Columbia could one day be home to such a greenhouse gas-absorbing mine.

A preliminary assessment completed in 2020 outlines plans for a mine at Turnagain that could produce 33,215 metric tons of the nickel and 1,962 metric tons of the cobalt needed for EV batteries annually for 37 years.

It just so happens that the tailings left behind after the nickel and cobalt extracted from the ore at Turnagain are really good at absorbing CO2 out of the atmosphere.

Dipple said an initial four-week test of Turnagain material showed a mine at Turnagain could absorb roughly 900,000 metric tons of CO2 over the life of the operation, or 0.72 metric tons of CO2 per metric ton of nickel produced.

This would offset nearly all the 0.75 metric tons of CO2 that is expected to be emitted per metric ton of nickel if an electric mining fleet was used to do the digging and hauling.

Dipple's testing indicates that these CO2 absorption rates would be higher under actual mining scenarios.

"A second sample was tested with periodic mixing of the tailings layer, reflecting potential active management of a tailings facility; this second sample showed a sustained increase in carbon sequestration rates of 25%," he said. "During periods of optimal moisture and mixing, the sequestration rates increased up to three times the long-term average."

The testing also showed that only about 10% of the brucite – a magnesium hydroxide mineral in ultramafic rocks at Turnagain that is responsible for sponging atmospheric CO2 – was consumed during the one-month sequestration test, indicating that Turnagain mine tailings would absorb more of the greenhouse gas with longer exposure to the air.

More information on Turnagain and Dipple's work there can be read at Potential CO2 neutral nickel mine in BC in the June 2, 2021 edition of Metal Tech News.

Carbin Minerals will use the XPRIZE funding to further optimize and accelerate the proprietary technologies it has developed to allow mines that can turn atmospheric carbon into rocks on the gigaton-scale while also producing metals that go into cars without CO2-emitting tailpipes.

"By tapping into one of the largest carbon storage reservoirs on Earth, ultramafic rocks, we are working on a solution that will tangibly reduce the amount of carbon dioxide in our atmosphere and truly turn the dial on climate change," Carbin Minerals posted on its website.

A Carbfix for Tamarack Mine

Carbin Minerals is not the only XPRIZE-winning company developing technologies that can be used to turn CO2 into rock while at the same time producing metals needed for the EV revolution. Iceland-based Carbfix has developed its own approach to permanently storing CO2 as a carbonate mineral.

While Carbfix utilizes mafic rocks known as basalts to store solidified carbon, its pathway from atmosphere to lithosphere differs from Carbin Minerals.

The Carbfix process dissolves CO2 in water and then injects this sparkling water of sorts into the subsurface where it reacts with favorable rock formations to form solid carbonate minerals.

Because it is denser than the water occurring in most geological formations, the carbonated water sinks after being injected, preventing any CO2 gases from escaping and reentering the atmosphere while the acidic sparkling water reacts with the rocks and the carbon solidifies. A sort of antimining process that removes an element from the atmosphere and turns it into a mineral deposit in the lithosphere.

With this technology, Carbfix was the co-winner of two XPRIZEs for Carbon Removal.

"We're immensely honoured to receive such a solid recognition in this prestigious and highly competitive global competition," said Carbfix CEO Edda Sif Pind Aradóttir. "We've already been applying our method of underground CO2 mineralization for 10 years. Presently, we are aiming for significant upscaling of our tried and tested technology, an ambition which will be greatly supported by our XPRIZE success and our excellent partnerships in those projects."

Heirloom and Verdox, each with novel and innovative carbon capture technologies, were Carbfix' XPRIZE winning partners.

"Utilizing low cost, earth abundant minerals as both sponge and storage for CO2 is key to making the economics work. We're thrilled to partner with Carbfix as an XPRIZE Milestone 1 winner and turn our Phase 1 idea into reality," said Heirloom CEO Shashank Samala.

"We launched Verdox two years ago on the promise of our novel electrochemical carbon capture system, which has been shown to reduce the energy penalty for capture by up to 70%," added Verdox CEO Brian Baynes. "XPRIZE's recognition of Verdox and Carbfix's combined potential is yet another signal that the future of carbon removal will be electric."

The Carbfix solution has also attracted the attention of the U.S. Department of Energy, which announced earlier this year it is investing $2.2 million to study the potential of applying this technology at the Tamarack nickel-copper mine in Minnesota.

Global mining company Rio Tinto is leading this three-year research and development project investigating the carbon storage potential at Tamarack, which is being advanced by a joint venture between Rio Tinto (49%) and Talon Metals Corp. (51%).

"Rio Tinto has assembled a uniquely qualified team of scientists and innovators to explore new approaches to harness carbon mineralization as a way to safely and permanently store carbon sourced from hard-to-abate industries and carbon removed from the atmosphere," said Talon Metals CEO Henri van Rooye.

Carbfix

The white crystals are precipitated carbonates in core from drilling at a Carbfix carbon dioxide injection site in Iceland.

More information on the carbon capture technology being developed for Tamarack can be found at DOE funds carbon antimining at Tamarack in the February 23, 2022 edition of Metal Tech News.

The innovative CO2 sequestration thinking being considered makes Tamarack an attractive source of the metals needed for the EVs being produced by Tesla, which has entered into a preliminary agreement to acquire 165 million lb of nickel per year from a future mine at the project.

Through the purchase agreement by Tesla and the XPRIZE awards to Carbfix, Musk is helping to create the holy grail of clean energy projects – a mine that turns CO2 to stone while supplying the metals vital to building EVs that have zero tailpipes to emit greenhouse gasses.