Environmental evaluation of metals and minerals production based on a life cycle assessment approach: A systematic review

Many metals and minerals are the backbone of the clean energy transition. However, its extraction and pro-duction are known to be a source of various environmental impacts. The use of a multicriteria assessment tools such as life cycle assessment (LCA) to evaluate the environmental impacts of the production of these elements is still poorly developed. Therefore, science-based decisions to achieve carbon neutrality are limited as the whole life cycle is generally not considered. This systematic review was conducted to analyse three main aspects: (i) the context of LCA application in the mining industry, (ii) the methodology followed by LCA practitioners in liter-ature, and (iii) the environmental impacts of different metals and minerals in multiple contexts. Seventy-eight (78) papers studying the life cycle of different metals and minerals were analyzed. The results of the method-ology adopted in literature show some tendencies in terms of functional unit, system boundary, data source and software used. Among the studied elements, gold showed the highest impact in the global warming potential (GWP), terrestrial acidification (TP), water depletion (WD) and land use (LU). In the other hand, the comparison of those elements' global carbon footprint in 2021 showed that coal has scored the highest impact at 1.49x109 t CO2 eq. This study highlights also the need to conduct more LCA studies on strategic metals (Li, Co, Mn, REE) for the clean energy transition to reach the net zero carbon target. Moreover, a comparative analysis between the reported data in the Ecoinvent database and the average values extracted from literature showed aligned results for GWP while it reveals a gap for the other indicators.

Automated summary

Through the analysis of 78 research papers on the life cycle of metals and minerals, this study reveals issues in the application context, methodology, and environmental impacts of life cycle assessment in the mining industry. The results show that gold has the highest impact on global warming potential, terrestrial acidification, water depletion, and land use, while coal has the highest global carbon footprint. The study highlights the need for more life cycle assessment studies on strategic metals for the clean energy transition.