LCA analysis and comparison in quarrying: Drill and blast vs mechanical extraction

Abstract

The production of mineral resources from quarrying is vital and irreplaceable for providing raw materials for a wide range of economic sectors. Additionally, today's society demands a supply of mineral resources that is as sustainable as possible. This paper presents a comprehensive LCA study comparing two commonly used techniques to extract mineral resources for quarrying, using the cradle-to-gate approach. The global warming potential (GWP) is used as the main indicator, although all the other potential emissions from the extraction process are also calculated. The results obtained reveal that blasting techniques have a lower impact on global warming (−28%) and generate less fuel metal emissions (−75%) than mechanical extraction. However, the emissions of PM2.5, PM10 and TSP are 2–3 times higher. Hence, the most optimal type of quarrying, regarding the environmental constraints, depends on the impacts in each specific case. In all of the scenarios analysed, the ore loading and handling stage is one of the main GWP contributors, while the contributions of the extraction system (e.g., mechanical or drill and blast) and mineral processing vary depending on the extraction technique used and the product analysed (e.g., aggregates or natural stone). The suggested approach can be used as a powerful tool to assess each case and determine the best choice regarding the environmental impacts of the mineral extraction process, as well as to reduce its emissions.