Direct extraction lithium processes: the challenges of spent brine disposal

Author(s): 
Ignacio Ezama, Camilo de los Hoyos, Pablo Cortegoso, Terry Braun
Date: 
Tuesday, October 2, 2018
First presented: 
Tailings and Mine Waste Conference 2018
Type: 
Published paper
Category: 
Other
 

The significant role of lithium in the continued development and expansion of renewable and clean energy has led to an increase in the demand for projects involving the extraction of lithium from shallow brines, particularly in the ‘lithium triangle’ – Salar de Atacama in Chile, Salar de Uyuni in Bolivia and Salar de Hombre Muerto in Argentina – to be developed.

In line with increased demand, several companies have developed direct extraction processes and new technology to recover the lithium contained in brine. These direct extraction processes have emerged as an alternative to the conventional processes that are based on increasing the concentration of lithium through solar evaporation in evaporation ponds.  The advantages of direct extraction processes include lower costs, shorter ramp-up periods and reduced dependence on climate.

However, management of spent brine tailings can be a significant issue if planning is inadequate. Direct extraction processes generate large amounts of spent brine (brine with a reduced lithium concentration), which may potentially affect the lithium-rich brine concentration.  To prevent tailings disposal from affecting the lithium-rich brine, diligent engineering design is required.  A key aspect in achieving cost-efficient direct extraction processes is providing solutions that avoid extensive use of liner in the disposal ponds or high operational costs.

This paper showcases recent experience with spent brine tailings management at projects in the lithium triangle, and experience in brine potash projects, which are similar in terms of mining methodology.

Click here to view the corresponding presentation

Feature Author

Ignacio Ezama

Ignacio Ezama is a Senior Consultant in SRK Salta. He has been involved in the development of numerous major geotechnical structures from scoping through to detailed design and construction, with practical experience in site selection, field investigation and geotechnical characterization, the design of embankments and other geotechnical structures including the assessment of risks related to hydraulics and seismicity. As part of the Mine Waste team, Ignacio has worked on projects involving a broad scope of tailings management, including thickened, dry stack, cyclone, co-disposal and conventional tailings covering a variety of commodities in both tropical and arid climates around the world.

Civil Engineer
Senior Consultant (Geotech and Mine Waste)
SRK Salta
Camilo Raúl de los Hoyos

Camilo de los Hoyos is a PhD in Geological Sciences and Senior Consultant Geologist at SRK´s Mendoza office with over 12 years of experience in water resource assessment, environmental geochemistry, lithium-potassium brine exploration in salars and igneous/metamorphic petrology. He has participated in several small- and medium-scale water resource projects in Argentina, Bolivia and Venezuela.

He has extensive experience in Acid Rock Drainage and Metal Leaching (ARDML) assessment as well as ARD treatment and mine waste remediation programs. Camilo´s experience in lithium-potassium brines includes comprehensive resource exploration programs, geological exploration/assessment of materials for brine processing and Technical Due Diligence. 

His Doctoral Thesis on geochemistry, isotope geochronology and geothermobarometry was applied to petrology and geotectonic.

Environmental Specialist
PhD
SRK Mendoza
Pablo Cortegoso
Pablo Cortegoso is a Civil Engineer with over 8 years of experience in civil and mining projects; specializing in lithium brine projects. His main areas of focus are surface water hydrology and modeling, project management, design and implementation of field programs and data collection and analysis for hydrogeological and geotechnical studies. Mr. Cortegoso has extensive experience in hydrogeological field programs, with an emphasis on lithium brine deposits, including well designs, packer testing and aquifer tests. Mr. Cortegoso expertise includes solar pond evaporation design, modeling and operation for lithium and potassium brine projects. Mr. Cortegoso has been a key member in the preparation and completion of Technical Due Diligences, Technical Reports (Mineral Resource and Reserve Statements), Preliminary Economic Assessments, Pre-Feasibility and Definitive Feasibility Studies in accordance with NI 43-101 and JORC Guidelines for lithium brine projects throughout Argentina, Chile, USA, UK and Botswana.

 

Lithium Project Development Specialist
MSc Civil Engineering
SRK Denver
Terry Braun

Terry Braun has over 25 years of professional experience in mining and environmental projects. His practice incorporates various elements of environmental compliance activities as well as engineered solutions to potential environmental liabilities at mining and other industrial operations. He develops and often implements projects that require negotiations with regulatory agencies and other stakeholders to achieve client objectives. Terry leads multi-disciplinary project teams tasked with producing engineering studies in accordance with public disclosure requirements (i.e., Canada and U.S.) as well as internal due diligence reviews on behalf of clients. His project experience includes planning, permitting and implementing the large-scale closure program for the BHP Copper San Manuel mine and plant sites in Arizona. He has also led teams in mitigating legacy mining impacts at active and inactive mine properties in the western U.S.

Principal GeoEnvironmentalist
MSc, PE
SRK Denver
SRK Africa