Published on July 19th, 2020 | by Steve Hanley0
Lithium Can Be Extracted From Groundwater At Geothermal Installations
July 19th, 2020 by Steve Hanley
Scientists at the KIT Energy Center at the Karlsruhe Institute of Technology say there is enough lithium dissolved in the groundwater extracted by German geothermal heating and electricity installations to meet the needs of most if not all of the battery manufacturers in the country. “As far as we know, there can be up to 200 milligrams per liter,” says geoscientist Dr. Jens Grimmer of the Institute of Applied Geosciences at KIT. “If we consistently use this potential, we could cover a considerable part of the demand in Germany.”
The implications are enormous. Today, Germany has a number of battery factories in operation or under construction to supply the needs of its domestic auto industry. BASF announced last year it was building a new factory in Brandenburg, not far from the new Tesla factory. CATL is constructing its first European factory in Erfurt. Concerned about Asian companies dominating the supply of batteries for its automakers, Germany has earmarked €2 billion to encourage German companies to build battery factories in the country. A local source of lithium would provide a big boost to those plans.
The lithium needed to manufacture the battery cells that power electric vehicles comes mostly from Chile, Argentina, and Australia. Developing a supply within Germany would be an important step forward in avoiding any of the supply issues that can arise when the primary source of a critical element is half a world away.
There are other considerations. In Chile, the lithium is contained in salt lakes and can take months to extract from the brine. In Australia, it is obtained from rocks using traditional mining techniques that require a significant disturbance of the land and leave lots of waste material — politely known as “overburden” in the industry — behind. By contrast, extraction of lithium from the groundwater used by geothermal heating and electricity plants can begin within hours. There is no overburden to contend with, the effect on the heating or electrical generation operations of the geothermal plants is minimal, and no carbon dioxide is added to the atmosphere in the process..
“We export many environmental problems to third countries in order to maintain and improve our living standards. With this process, we can assume our responsibility and extract important raw materials for modern technologies in an environmentally friendly way right on our own doorstep,” says Dr. Florencia Saravia from the research unit of the German Technical and Scientific Association for Gas and Water (DVGW). “We can also build up regional value chains, create jobs, and reduce geopolitical dependencies at the same time.”
The geothermal plants in the Upper Rhine Trench use several billion liters of groundwater a year, which means each one could produce hundreds of toms of lithium annually. Together, all the geothermal facilities in German and France that extract hot water from beneath the Upper Rhine Trench could supply thousands of tons of lithium to European battery manufacturers.
Currently, there are 34 geothermal energy plants operating in Germany. 25 of them produce heat, 4 produce electricity, and 5 are combined geothermal power plants providing both heat and electricity. In total, the plants produce about 300 MW of heat output and 42 MW of electricity. According to the German Geothermal Association, there are plans to build another 30 geothermal facilities in Germany, many of which will combine heat and electrical output to maximize their profit potential.
Until now, there was no cost effective way to extract lithium from the groundwater geothermal facilities process to make heat or electricity. The Grimmer/Saravia process hopes to change that. “In a first step, the lithium ions are filtered out of the thermal water and in a second step, they are further concentrated until lithium can be precipitated as a salt,” says Grimmer. The lithium precipitate is produced in only a few hours. KIT has applied for a patent based on the work of the two scientists. A pilot “proof of concept” program is taking place at one geothermal facility. If it proves successful, a larger commercial scale installation will follow.
There are other commercial applications involved. The Grimmer/Saravia process can also capture other valuable elements such as rubidium or cesium from the thermal water, increasing the commercial importance of the discovery.
Electric car detractors like to point out that making batteries is a carbon intensive process (as if the extraction of oil and gas is not!) and automakers are keen on reducing the environmental impact of making EVs. Sustainability is a major consideration at Volkswagen and BMW these days. The ability to obtain lithium from local sources in a manner with few environmental implications would be a huge plus for those companies.
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