Brine

A start-up company will announce on Wednesday that it is beginning commercial operations at a factory in Southern California to capture lithium from existing geothermal energy plants, a technology it says has the potential to turn the United States into a major lithium exporter. 

The plant, built by Simbol Materials near the Salton Sea in the Imperial Valley, will also capture manganese and zinc.  None of the materials that Simbol plans to produce are so-called rare earths, but 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. The society considers them “energy critical elements.”

Lithium is a crucial element for batteries that power electric cars, and manganese is used in batteries and in specialty metal production. The United States imports much of its lithium and does not produce any manganese at all.

The company, based in Pleasanton, Calif., will piggyback on an existing geothermal plant that makes electricity by pumping hot water from deep underground and using its heat to make steam to drive a turbine. Then it re-injects the water into the ground. The “water” is actually a very strong brine, composed of about 30 percent dissolved salts, according to Luka Erceg, Simbol’s co-founder and chief executive.

Simbol officials say they have developed a proprietary filtering process that takes minutes and will be located on piping that is a minor detour for brine that the geothermal energy company is pumping anyway. Costs are low enough to compete in the world market, company officials say, and environmental impacts are small since the geothermal plant is already in operation.

The plant will process 5,000 to 6,000 gallons of water a minute, and in the same period will produce 10 to 20 gallons of salts that include the marketable metals. Since last October, Simbol has been running a modest pilot plant that filters about 20 gallons a minute, Professor Jaffe said. The brine from the Salton Sea contains lithium in a concentration of 200 to 400 parts per million, and the extraction technology is about 93 percent efficient, he said.