California startup Simbol Materials thinks it can increase domestic production of lithium by extracting the element, along with manganese and zinc, from the brine used by geothermal plants. The technology, it says, has the potential to turn the United States into a major lithium exporter.
Portable electronics and electric cars both need a steady supply of lithium. It is expected that lithium demand goes up to as much as 320,000 tons by 2020, mostly because of increased electric-vehicle use. A study by the American Physical Society in February identified lithium and zinc as likely to be very important in the new energy economy of the future.
But lithium isn’t rare. Quite the opposite. It’s the 25th most abundant element on earth, close to nickel and lead. Bolivia has 35% of the world’s lithium resources, but Chile and Australia dominate the worlds lithium production. Hardly any lithium is produced in the U.S, only 5 %. At the moment, lithium producers pump mineral-rich brine from the beneath the earth’s surface into giant pools. Then the brine evaporates in the sun for up to two years, leaving lithium chloride behind. From there on the lithium is taken away to be processed elsewhere.
Simbol Materials aims to use brine from a existing 50-megawatt geothermal plant near California’s Salton Sea. The plant makes electricity by pumping hot water from deep underground and using its heat to make steam to drive a turbine. The plant currently injects the brine, which contains 30 percent dissolved solids, including lithium, manganese, and zinc, back into the ground after the steam is produced. Simbol’s will now extract the elements before pumping it back into the ground. This process only takes two hours instead of two years. A major improvement, so it seems. Simbol Materials expects to compete with the lowest-cost Chilean lithium producers, which produce lithium at $1,500 a ton while keeping it as environmentally-friendly as possible.