Lithium extraction from geothermal fluids
Lithium was first discovered in Cornwall in 1864 by Miller, an academic at Queen’s College London who was intrigued by the hot springs encountered in the Cornish mines. These hot springs occur when saline geothermal fluids circulate through fractures and faults within the granites, and discharge from the crosscourse structures and mineralised lodes due to the natural permeability of structures relative to the surrounding rock.
Miller performed the first geochemical analysis on a fluid sample taken from the Hot Lode at United Downs. The geothermal fluid was notable for its temperature of 1240F at 230 fathoms depth (equivalent to 510C at 420m depth). The hot springs were often 10 degrees higher in temperature than the rock temperature at the depth they were encountered, suggesting that they had travelled from a deeper source. When these geothermal waters were tested, they were found to be ‘extremely rich in lithia’ – of academic interest in 1864, but not commercial interest. Further geochemical analyses of these hot springs at South Crofty in the 1980s confirmed the presence of consistent levels of lithium enrichment in the fluids, at concentrations which can now be economically extracted directly from the geothermal fluids by use of new technologies which have been developed in the past few years.
Lithium Extraction Techniques
Recent advances in technology mean that it is now possible to economically extract lithium directly from fluids, in the concentrations historically present in Cornwall’s hot springs. Various companies have developed their own proprietary extraction technologies; Cornish Lithium are in discussion with potential partners to work out which may be best suited to extract lithium from Cornish geothermal fluids.
Contained within thermal springs, in 2015 subsurface brines yielded about half of the world’s lithium production
Recently developed technology allows lithium extraction from brine over a very short period of time yielding up to 99.9% purity
Rechargeable lithium-ion battery consumption is driving strong demand growth for the foreseeable future
Cornish Lithium has recognised the commercial potential of lithium contained in geothermal brines in Cornwall
Demand for Lithium has never been stronger, with Goldman Sachs calling it “the new gasoline” and suggesting demand could triple by 2025
The time is right for the creation of a new lithium extraction industry for Cornwall
Cornish Lithium is undertaking the largest single unified exploration programme in Cornwall’s history
Rights have been secured to explore for and commercially extract lithium and develop geothermal energy contained in the Cornish hot springs