One of the main challenges facing Chile’s new lithium strategy is to incorporate technologies to achieve better recoveries and reinject the brine into the salt flats with a focus on maximizing the sustainability of the resource and reducing the impact on surrounding territories and ecosystems.
This implies replacing the current concentration and purification techniques that use evaporation ponds at the operations of local firm SQM and US company Albemarle, the only two lithium producers in the country, in the Salar de Atacama in northern Chile.
“We hope to start the tests in August to see if technically both [extraction and reinjection] are feasible and analyze how the salt works with the brine and the chemical qualities that will be reinjected,” said Ignacio Mehech, VP of external affairs at Albemarle Chile, in reply to a question from BNamericas during an online seminar hosted by the Universidad de Las Américas’ school of biotechnology and the environment on Wednesday.
Mehech commented that they already have the environmental authorization and that the results will be published after a 3-4 month evaluation process.
Direct lithium extraction (DLE) is superior to conventional ponds in aspects such as recovery, selectivity and brine reinjection, as well as being faster than the water evaporation process, which after 14 to 18 months achieves product separation. However, it is more intensive in the consumption of water and electricity.
To help compensate for the increases that the new technology would bring in operating costs, Albemarle has closed an agreement with CRAMSA to obtain up to 500l/s of desalinated water from 2027. “It will allow us to analyze the implementation of direct extraction methods of lithium in our Salar de Atacama plant,” Mehech said.
Albemarle estimates that global demand for the white metal will grow five times by 2030, reaching 3.7Mt of lithium carbonate equivalent. “Almost one in two vehicles will be electric,” he predicted, adding that in recent years demand has risen constantly.
For this reason, in addition to improving the performance of its La Negra phase III chemical plant last year to increase its production, the company invested US$150mn in a lithium recovery efficiency project that will start operations this year and “will salvage more lithium from salts like carnallite and bischofite,” the Albemarle representative said.
Unlike the salts present in seawater that reach about 4% or in drinking water that is 0.05%, brine is made up of 20% salts. This implies that there could be much more lithium contained in the salts, Nancy Parada, a chemical engineer and member of the Chilean chamber of mines, told the event, stressing the need to continue researching new extraction alternatives.
Through the new technologies, higher recoveries of other compositions that are present in the salt flats of Chile, such as sodium, potassium, magnesium, calcium, sulfate, chloride and boron, would also be achieved.
Chile is the second largest lithium producer in the world and has the largest reserves. The new national strategy points to sustainability and greater added value in the metal’s chain.
Source : Bnamericas