Fast, low-cost direct lithium extraction could avert a supply crisis
Canadian company Volt Lithium has developed and pilot-tested a new low-cost lithium extraction method to pull this critical battery metal out of low-concentration brines. Now it plans to turn old oil fields into lithium production operations.
As the global transition to electric vehicles gathers momentum, and power grids worldwide turn to huge banks of batteries to balance demand against the intermittent supply of renewables, the world is going to need unprecedented amounts of lithium to fuel its insatiable hunger for batteries.
We've written before that many people are expecting a lithium squeeze in the coming decade; it takes around 13 years to start up a new mining operation, for example, and the International Energy Agency projects that existing mines and brine projects, plus those currently under construction, are only going to deliver about half of the projected demand.
Direct Lithium Extraction (DLE) offers a "potentially revolutionary" way to quickly and cheaply boost production from brine "much like shale did for oil," according to a Goldman Sachs report from April.
The typical way to extract lithium from salty groundwater brine is to pump it up from underground, then sit it in gigantic ponds on the surface. Over the course of a year or more, the Sun gently evaporates the water away until the lithium concentration can be precipitated out with chemical reagents and processed into lithium carbonate or hydroxide for sale. Operating this way, you can extract 40-60% of the lithium in your brine at a cost between US$3,300 and US$4,900 per metric ton of lithium carbonate equivalent.
The DLE process is much faster, taking a matter of hours instead of more than a year. It can pull up to twice as much lithium out of a given brine as an evaporative process, potentially doubling the output of a given brine operation. It uses about 95% less land, and is economically viable with considerably lower lithium concentrations in the brine. And it costs less per ton of lithium carbonate equivalent than evaporation.
Essentially, the DLE process involves adding a highly selective absorbent molecule to the brine, which captures the lithium and quickly separates it from the water, rejecting impurities in the process.
Calgary's Volt Lithium is one of many companies pushing forth on this potentially game-changing technology. Volt announced earlier this year that its pilot program had managed to extract 90% of the lithium from concentrations as low as 34 mg/liter, and a stellar 97% from concentrations of 120 mg/liter.
The latter figure is significant, as that's the concentration of lithium in the brine under the company's 430,000 acres of land at Rainbow Lake, Alberta. This is an old, depleted oil field with more than 1,300 well bores pre-drilled on the site for easy access to the brine. Volt estimates there's about 4.9 million metric tons of lithium carbonate equivalent there for the plundering, and that it can do so for around US$3,000 per metric ton, pumping out about 20,000 tons a year.
"This technological discovery opens up multiple oilfield reservoirs across North America that can now offer commercial lithium extraction using Volt's proprietary DLE process," reads a company press release. The release also notes that relatively simple process improvements like optimizing the usage of reagent should reduce costs further. The company is moving to establish its first permanent pilot plant.
Brine makes up around two thirds of global lithium resources, according to Goldman Sachs, but only about 40% of current production. If DLE technologies are rolled out through 20-40% of the brine operations in Latin America, raising their yields from ~50% to ~80% conservatively speaking, then by 2028, Goldman Sachs estimates that would put 70-140,000 tons more lithium onto the market, boosting the global raw supply by around 8%.
That's not enough to meet the expected demand in 2030, but it also doesn't take into account the new oilfield extraction opportunities across North America, Asia and Europe that emerging technologies like Volt's are unlocking.
Source: Volt Lithium