Environmental impact assessment of direct lithium extraction from brine resources: Global warming potential, land use, water consumption, and charting sustainable scenarios

Abstract

Direct Lithium Extraction (DLE) has emerged as an alternative that bypasses lengthy evaporation processes to produce lithium from brine sources. This study scrutinizes both direct and indirect environmental impacts of DLE, specifically focusing on global warming, land use, and water consumption in Clayton Valley, Nevada. It was compared to traditional brine and hard rock extraction methods. The DLE method is closely tied to energy usage, and this study has explored various scenarios for power sources. The TRACI, ReCiPe, and AWARE methods of life cycle assessment were employed to evaluate the environmental footprint, indirect land use, and water footprint of lithium production from various sources. According to the study, producing one ton of lithium carbonate using the DLE method showed distinct emissions profiles. Specifically, when electricity was sourced from a diesel generator, the Nevada grid, or solar panels, the emissions totaled approximately 22, 17.3, and 7.6 tons of CO2eq, respectively. Switching power sources goes beyond affecting greenhouse gas emissions; it also influences land use impacts and individual water consumption, as evaluated in this study. The direct land use for DLE is as follows: 16, 493, 182, and 659 m²/ton of Lithium Carbonate Equivalent (LCE) for processing plant, processing plant, well field, processing plant, solar panel area, and all regions required with solar panels, respectively. In assessing the water footprint, the study determined varying water deprivation potentials depending on the electricity source utilized: 3.7 m³eq/kg of LCE with a diesel generator, 9.5 m³eq/kg of LCE with the Nevada grid, and 4.2 m³eq/kg of LCE with solar panels.